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What does a high-pressure water relief valve do on a water pump?

Views: 1446     Author: Site Editor     Publish Time: 2022-03-12      Origin: Site

A relief valve or pressure relief valve (PRV) is a type of safety valve used to control or limit the pressure in a system

On positive displacement pumps, a relief valve is normally required:

Relief valve is always required for the positive displacement pump as it can theoretically generate infinite pressure when its discharge valve is closed and pump is in operation. This can be very well verified by the performance curve of the pump where graph of Q vs H is vertical. Relief valve at the discharge of the pump is required to protect the pump and discharge pipe and its components due to overpressure caused by the pump. A positive displacement pump will attempt to discharge a defined volume of fluid per revolution, irrespective of discharge pressure. Fluid being non compressible, this necessitates that the hydraulic circuit incorporate an overpressure relief valve.

In case of centrifugal pumps, no such relieving arrangement is fitted:

A centrifugal pump is not a positive displacement pump. So, they can run against a closed outlet and then produce the locked outlet pressure. But no harm will be done. The liquid will circulate inside the pump, the power requirement will drop as there is no displacement, but that's it. to be simple and short, non-positive displacement pumps don't develop or keep adding pressure when the exhaust in closed (this is not possible in positive displacement pumps like reciprocating pumps etc.). Thus, in centrifugal pump the excess pressure possibility is reduced thereby eliminating the need of a relief valve.

The high pressure relief valve with our high pressure piston pump:


A relief valve is an automatic pressure release device used on pressure equipment, containers or pipelines. It is used to automatically open when the medium pressure of the equipment or pipeline rises and exceeds the specified value. It prevents the pressure of the medium in the pipeline or equipment from exceeding the specified value by discharging the medium to the outside of the system.


1. Beautiful appearance, small size

2. Easy to install and disassemble

3. Simple and convenient pressure adjustment

4. Stable pressure and flow output

5. Either as a safety valve or as a pressure regulating valve

If you’re interested in further details or information, you can:

Visit our detailed accessories page for the relief valve.